A beach on Auckland's North Shore remains closed after a major leak sent sewage through two houses yesterday.
Residents evacuated from two Auckland houses after they woke up in the early hours with sewage flowing through rooms.
A leak in a large pipeline carrying sewage led to the evacuation of six houses in Milford on the North Shore.
Trucks were lined up in Alma Road and 35 Watercare staff and contractors - many in full white protection suits - worked on the clean-up in the blazing sun.
Two households were woken around 3am on Sunday with sewage flowing through the rooms.
Up to half a dozen others had filthy water in their gardens.
Public health warning signs were keeping people out of the water for the second time in a week, but Auckland Council did not know if the water is contaminated or not.
Safeswim technical leader Martin Neale said no water samples were taken yesterday because testing labs were closed on Sundays.
He said it would take about 18 hours before he had any results from samples he took this morning.
"The sewer pipe break would have discharged to Wairau Creek which discharges or flows over the northern end of Milford beach.
"So the sewage would have made it to the beach at some point yesterday.
"What we don't know is how widespread and what the effects of that would have been so that's why we've been taking samples today."
Watercare acting chief operations officer Mark Bourne visited the affected area.
"There are two properties that have been affected in terms of sewage contamination inside their homes and these things are very distressing when they occur.
"We have to work very closely and compassionately with those properties that are affected."
The affected residents were staying in local motels and "realistically, it would take a day or two" before they could move back, he said.
"We have to work with their insurers and make sure appropriate cleaning measures are taking place before they can move into their homes."
Mr Bourne said evacuated residents who had sewage in their gardens should be back home by today.
Homeowners in the same street did not want to be named, but several said infrastructure in the area had struggled over recent years to keep pace with population growth due to infill housing.
A heavy downpour caused similar sewage overflow into Wairau Creek last week, which affected local Milford beach, one man said. This was not unusual.
Another local man said sewage overflows from the pumping station had been a regular occurrence since his grandmother lived here in the late 1950s.
"I remember her telling me when I was visiting as a kid: 'Today's not a day to swim at the beach because there's been an overflow'."
On Sunday, Milford beach was off-limits for swimmers because of the spill.
In practice many people enjoyed a great day at the water - unaware of the leak that could be pumping untreated waste into the sea.
Beachgoer Katie said she had been for a swim.
"I just arrived at the beach and noticed the sign and a lady told me it was still fine to swim, just so long as we were further down from where it happened. She said the leak was on land, so it would be fine to swim."
Andrew was more cautious.
"I just arrived. I haven't been in yet. I'm tossing it up, but I think I will go in."
The council put small warning signs at entrances to the beach, but nothing to indicate this sewage leak was anything out of the ordinary, he said.
Mr Bourne said Watercare was working with Auckland Council's Safeswim programme to monitor water quality. He said the warnings at the beach were more a precautionary measure at this stage.